Virtual white lines for indicating planned excavation sites on electronic images

ABSTRACT

Methods and apparatus for facilitating detection of a presence or an absence of at least one underground facility within a dig area. Source data representing one or more input images of a geographic area including the dig area is electronically received at a first user location, which may be remote from the dig area. The source data is processed so as to display at least a portion of the input image(s) on a display device at the first user location. One or more indicators are added to the displayed input image(s), via a user input device associated with the display device, to provide at least one indication of the dig area and thereby generate a marked-up digital image. In one example, the indicator(s) is/are added to the displayed input image(s) without acquiring geographic coordinates corresponding to the indicator(s).

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims a priority benefit, under 35 U.S.C. §120,as a continuation (CON) of U.S. patent application Ser. No. 12/366,853,filed Feb. 6, 2009, entitled “Virtual White Lines for Indicating PlannedExcavation Sites on Electronic Images.”

Ser. No. 12/366,853 claims a priority benefit, under 35 U.S.C. §120, asa continuation-in-part (CIP) of U.S. patent application Ser. No.12/050,555, filed Mar. 18, 2008, entitled “Virtual White Lines forDelimiting Planned Excavation Sites.”

Each of the above-identified applications is incorporated herein byreference in its entirety.

BACKGROUND

Excavators are required to notify underground facility owners in advanceof their excavation activities and to describe and communicate thegeographic area of those activities to the underground facility owners.The geographic area so described is commonly referred to as “the digarea.” In turn, facility owners (which, as used herein, may includefacility owners, operators, and/or their designated representatives) arerequired to determine if they own or operate any underground facilitiesat an identified dig area. The location of those underground facilities,if any, which exist within a dig area, is marked using paint or someother physical marking system, such as flags. The application of paint,flags, or some other marking object to indicate the presence of anunderground facility is called a “locate.” The marks resulting from alocate are commonly called underground facility “locate marks.”Underground facility owners may perform locates with in-house employeesor choose to hire independent contract locating firms to perform locateson their behalf as their designated representatives.

Currently, excavators may communicate with facility owners through “onecall centers.” These one call centers are generally owned, controlled,or funded by underground facility owners, such as telephone companies,cable television multiple system operators, electric utilities, gasutilities, or others. One call center operations may be managed by anon-profit entity or outsourced to a for-profit firm. Excavators arerequired to notify one call centers in advance of their excavationactivities and identify through a “locate request” the dig area whereindividual excavating activities will be performed. Locate requestsconsist of information supplied by the excavator to the one call centerregarding the specific geographic location of the dig area, date, time,purpose of excavation, etc. The locate request, in turn, requiresactivity from an underground facility owner to perform a locateoperation in the specified dig area.

One call centers may receive locate requests from excavators viaelectronic delivery or verbally through a telephone conversation betweenthe excavator and a human operator working for a one call center.Whether communicated electronically or verbally, excavators mustdescribe the planned geographic locations of dig areas. This descriptionis ultimately reduced to text, which, along with other data about alocate request, is communicated to the appropriate underground facilityowner or owners responsible for locating any underground facilitieswithin the dig area so described. Textual descriptions of dig areas canbe very imprecise as to exact physical locations. In addition, addresseswhich are provided may be unclear, not yet assigned, or only indicatingcross streets and vague descriptions of the extent of the dig area.

On occasion, information provided in the locate request is supplementedby the excavator, who travels to the actual dig area and physicallymarks the dig area in order to physically delimit the actual area to beexcavated. These marks are commonly made using chalk or paint, and aregenerally known as “white lines.” In some states, white lining the pathof excavation may be required by the responsible regulatory body.

SUMMARY

Various embodiments of the present invention are directed to methods,apparatus and systems for creating an electronic record relating to ageographic area including a dig area to be excavated or otherwisedisturbed. As part of the electronic record, the dig area is somehowidentified with respect to its immediate surroundings in the geographicarea. For example, to create such an electronic record, one or moreinput images relating to the geographic area including the dig area maybe utilized. For example, source data representing one or more inputimages of a geographic area including the dig area is received and/orprocessed so that the input image(s) may be displayed on a displaydevice. The dig area is then indicated in some manner on the displayedinput image(s) so as to generate one or more marked-up imagesconstituting at least a portion of the electronic record. In someimplementations of the inventive concepts disclosed herein, theelectronic record may include a variety of non-image information tofacilitate identification of the dig area (e.g., a text description ofthe dig area, an address or lot number of a property within which thedig area is located, geo-encoded information such as geographiccoordinates relating to the dig area and/or various aspects of thegeographic area surrounding the dig area, etc.). The marked-up image(s)and the non-image information may be formatted in a variety of mannersin the electronic record; for example, in one implementation thenon-image information may be included as metadata associated with themarked-up image(s), while in other implementations the marked-upimage(s) and the non-image information may be formatted as separate datasets. These separate data sets may be transmitted and/or storedseparately, but may nonetheless be linked together in some manner asrelating to a common electronic record.

In sum, one embodiment of the present invention is directed to a methodfor facilitating detection of a presence or an absence of at least oneunderground facility within a dig area, wherein at least a portion ofthe dig area may be excavated or disturbed during excavation activities.The method comprises: A) electronically receiving, at a first userlocation remote from the dig area, source data representing at least oneinput image of a geographic area including the dig area; B) processingthe source data so as to display at least a portion of the at least oneinput image on a display device at the first user location remote fromthe dig area; C) adding, via a user input device associated with thedisplay device and at the first user location remote from the dig area,at least one indicator to the displayed at least one input image toprovide at least one indication of the dig area and thereby generate amarked-up digital image; and D) electronically transmitting and/orelectronically storing information relating to the marked-up digitalimage so as to facilitate the detection of the presence or the absenceof the at least one underground facility within the dig area.

Another embodiment is directed to a computer-readable medium encodedwith instructions that, when executed on at least one processing unit,perform a method for facilitating detection of a presence or an absenceof at least one underground facility within a dig area, wherein at leasta portion of the dig area may be excavated or disturbed duringexcavation activities. The method comprises: A) electronicallyreceiving, at a first user location remote from the dig area, sourcedata representing at least one input image of a geographic areaincluding the dig area; B) processing the source data so as to displayat least a portion of the at least one input image on a display deviceat the first user location remote from the dig area; C) receiving userinput, via a user input device associated with the display device and atthe first user location remote from the dig area; D) generating amarked-up digital image based on the displayed input image, themarked-up digital image including at least one indication of the digarea based on the user input; and E) electronically transmitting and/orelectronically storing information relating to the marked-up digitalimage so as to facilitate the detection of the presence or the absenceof the at least one underground facility within the dig area.

Another embodiment is directed to a method for facilitating detection ofa presence or an absence of at least one underground facility within adig area, wherein at least a portion of the dig area may be excavated ordisturbed during excavation activities. The method comprises: A)electronically receiving source data representing at least one inputimage of a geographic area including the dig area; B) processing thesource data so as to display at least a portion of the at least oneinput image on a display device; C) adding, via a user input deviceassociated with the display device, at least one indicator to thedisplayed at least one input image to provide at least one indication ofthe dig area and thereby generate a marked-up digital image, wherein C)is performed without acquiring geographic coordinates corresponding tothe at least one indicator; and D) electronically transmitting and/orelectronically storing information relating to the marked-up digitalimage so as to facilitate the detection of the presence or the absenceof the at least one underground facility within the dig area.

Another embodiment is directed to at least one computer readable mediumencoded with instructions that, when executed by at least one processingunit, perform a method for facilitating detection of a presence or anabsence of at least one underground facility within a dig area, whereinat least a portion of the dig area may be excavated or disturbed duringexcavation activities, the method comprising: A) electronicallyreceiving source data representing at least one input image of ageographic area including the dig area; B) processing the source data soas to display at least a portion of the at least one input image on adisplay device; C) receiving user input, via a user input deviceassociated with the display device; D) adding, based on the user input,at least one indicator to the displayed at least one input image toprovide at least one indication of the dig area and thereby generate amarked-up digital image, wherein D) is performed without acquiringgeographic coordinates corresponding to the at least one indicator; andE) electronically transmitting and/or electronically storing informationrelating to the marked-up digital image so as to facilitate thedetection of the presence or the absence of the at least one undergroundfacility within the dig area.

It should be appreciated that all combinations of the foregoing conceptsand additional concepts discussed in greater detail below (provided suchconcepts are not mutually inconsistent) are contemplated as being partof the inventive subject matter disclosed herein. In particular, allcombinations of claimed subject matter appearing at the end of thisdisclosure are contemplated as being part of the inventive subjectmatter disclosed herein. It should also be appreciated that terminologyexplicitly employed herein that also may appear in any disclosureincorporated by reference should be accorded a meaning most consistentwith the particular concepts disclosed herein.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate one or more embodiments describedherein and, together with the description, explain these embodiments. Inthe drawings:

FIG. 1 is a diagram of a concept described herein;

FIG. 2 is a diagram of an exemplary network in which systems and methodsdescribed herein may be implemented;

FIG. 3 is a diagram of exemplary components of the user device of FIG.2;

FIG. 4 is a diagram of exemplary components of the central server ofFIG. 2;

FIG. 5 is a diagram of exemplary routines associated with the userdevice and/or central server of FIG. 2;

FIG. 6 is a flow diagram of exemplary activities of a central server formanaging a locate request;

FIG. 7 is a flow diagram of exemplary activities of a user device forsubmitting a locate request and for adding virtual white lines to aninput image;

FIG. 8 is a diagram of an exemplary data set that may be stored in thememory of a central server of FIG. 4;

FIG. 9 is a diagram of an exemplary user interface that includes virtualwhite line marking tools that may be presented via the user device ofFIG. 3;

FIG. 10 shows a sketch 1000, representing an exemplary input image;

FIG. 11 shows a map 1100, representing an exemplary input image;

FIG. 12 shows a facility map 1200, representing an exemplary inputimage;

FIG. 13 shows a construction/engineering drawing 1300, representing anexemplary input image;

FIG. 14 shows a land survey map 1400, representing an exemplary inputimage;

FIG. 15 shows a grid 1500, overlaid on the construction/engineeringdrawing 1300 of FIG. 13, representing an exemplary input image; and

FIG. 16 shows a street level image 1600, representing an exemplary inputimage.

DETAILED DESCRIPTION

The following detailed description refers to the accompanying drawings.The same reference numbers in different drawings may identify the sameor similar elements. Also, the following detailed description does notlimit the invention.

Overview

FIG. 1 is a diagram of an exemplary concept described herein. When alocate request is submitted by an excavator to a one-call center, it maybe beneficial for the excavator to delimit the particular geographiclocation of the proposed excavation, such as a dig area 100, in apermanent and reproducible manner. The delimited dig area 100 indicatesto a locate technician the extent of the boundaries where a locate is tobe performed at the request of the excavator. Physical white lines 110may be used to physically delimit the dig area 100. Physical white lines110 generally may consist of chalk or paint on the surface of the groundto identify the dig area 100 boundary. However, these physical whitelines 110 provide only a temporary indication of dig area 100, as thephysical white lines 110 may deteriorate or be eliminated over time bysuch events as precipitation, excessive pedestrian or vehicle traffic,erosion, the excavation process, or numerous other events.

In the example of FIG. 1, a locate technician may be requested by anexcavator to locate and mark underground facilities in dig area 100. Theprecise geographic extent of dig area 100 as communicated by theexcavator may be uncertain. This uncertainty as to the precise extent ofdig area 100 may result in a locate operation which does not address theentirety of the planned excavation site or conversely may result in alocate operation which covers an area in excess of the precise extent ofthe planned excavation area. When performing the locate operation thelocate technician may use paint, flags, or some other object with aparticular color or other characteristic to mark the location of anunderground facility. Referring to the example shown in FIG. 1, thelocate technician may be required to mark a portion of underground powerline 120 that lie within the dig area 100. However, the locatetechnician may not be required to mark the portion of underground powerline 120 that lies outside the dig area 100 or telecommunications line130 that lies outside the dig area 100. Additionally, telecommunicationline 140 traverses only a small portion of dig area 100. Without aprecise and certain description of dig area 100, the small portion oftelecommunication line 140 within dig area 100 may not be located by thelocate technician as the technician may believe that the presence oftelecommunication line 140 is not of interest to the excavator. Thus, itis important that the locate technician is provided a clear and accurateboundary of dig area 100 to avoid, for example, an excavator laterdigging over an unmarked underground facility. Physical white lines 110placed by the excavator and/or descriptive text provided by the one-callcenter may be used to delimit the dig area 100. However, as noted above,these methods may lack permanency, accuracy, or certainty.

In view of the foregoing, various embodiments of the present inventionare directed to methods, apparatus and systems for creating anelectronic record relating to a geographic area including a dig area tobe excavated or otherwise disturbed. As part of the electronic record,the dig area is somehow identified with respect to its immediatesurroundings in the geographic area. For example, source datarepresenting one or more input images of a geographic area including thedig area is received and/or processed so that the input image(s) may bedisplayed on a display device. The dig area is then indicated in somemanner on the displayed input image(s) so as to generate one or moremarked-up images constituting at least a portion of the electronicrecord. In some implementations of the inventive concepts disclosedherein, the electronic record may include a variety of non-imageinformation to facilitate identification of the dig area (e.g., a textdescription of the dig area, an address or lot number of a propertywithin which the dig area is located, geo-encoded information such asgeographic coordinates relating to the dig area and/or various aspectsof the geographic area surrounding the dig area, etc.). The marked-upimage(s) and the non-image information may be formatted in a variety ofmanners in the electronic record; for example, in one implementation thenon-image information may be included as metadata associated with themarked-up image(s), while in another implementation the marked-upimage(s) and the non-image information may be formatted as separate datasets. These separate data sets may be transmitted and/or storedseparately, but may nonetheless be linked together in some manner asrelating to a common electronic record.

An exemplary displayed input image 150 is shown in FIG. 1 (the inputimage is displayed on a laptop computer 170). The displayed input imageprovides a view of the geographic area surrounding dig area 100. Variousembodiments relating to the inventive concepts disclosed herein enableexcavators, one-call centers, or other users to indicate the dig area onone or more displayed input images. For purposes of the presentdisclosure, an input image is any image represented by source data thatis electronically processed (e.g., the source data is in acomputer-readable format) to display the image on a display device. Aninput image may include any of a variety of paper/tangible image sourcesthat are scanned (e.g., via an electronic scanner) or otherwiseconverted so as to create source data (e.g., in various formats such asXML, PDF, JPG, BMP, etc.) that can be processed to display the inputimage. An input image also may include an image that originates assource data or an electronic file without necessarily having acorresponding paper/tangible copy of the image (e.g., an image of a“real-world” scene acquired by a digital still frame or video camera orother image acquisition device, in which the source data, at least inpart, represents pixel information from the image acquisition device).

In some exemplary implementations, input images according to the presentdisclosure may be created, provided, and/or processed by a geographicinformation system (GIS) that captures, stores, analyzes, manages andpresents data referring to (or linked to) location, such that the sourcedata representing the input image includes pixel information from animage acquisition device (corresponding to an acquired “real world”scene or representation thereof), and/or spatial/geographic information(“geo-encoded information”). In this manner, a GIS provides a frameworkfor data manipulation and display of images that may facilitate one ormore of (a) location verification, (b) location correlation, (c)locational relationships, (d) district coding, (e) route analysis, (f)area analysis and (g) mapping/display creation, for example.

In view of the foregoing, various examples of input images and sourcedata representing input images according to the present disclosure, towhich the inventive concepts disclosed herein may be applied, includebut are not limited to:

-   -   Manual “free-hand” paper sketches of the geographic area (which        may include one or more buildings, natural or man-made        landmarks, property boundaries, streets/intersections, public        works or facilities such as street lighting, signage, fire        hydrants, mail boxes, parking meters, etc.). FIG. 10 shows an        exemplary sketch 1000;    -   Various maps indicating surface features and/or extents of        geographical areas, such as street/road maps (e.g., map 1100 of        FIG. 11), topographical maps, military maps, parcel maps, tax        maps, town and county planning maps, call-center and/or facility        polygon maps, virtual maps, etc. (such maps may or may not        include geo-encoded information);    -   Facility maps illustrating installed underground facilities,        such as gas, power, telephone, cable, fiber optics, water,        sewer, drainage, etc. Facility maps may also indicate        street-level features (streets, buildings, public facilities,        etc.) in relation to the depicted underground facilities.        Examples of facility maps include CAD drawings that may be        created and viewed with a GIS to include geo-encoded information        (e.g., metadata) that provides location information (e.g.,        infrastructure vectors) for represented items on the facility        map. An exemplary facility map 1200 is shown in FIG. 12;    -   Architectural, construction and/or engineering drawings and        virtual renditions of a space/geographic area (including “as        built” or post-construction drawings). An exemplary        construction/engineering drawing 1300 is shown in FIG. 13;    -   Land surveys, i.e., plots produced at ground level using        references to known points such as the center line of a street        to plot the metes and bounds and related location data regarding        a building, parcel, utility, roadway, or other object or        installation. FIG. 14 shows an exemplary land survey map 1400;    -   A grid (a pattern of horizontal and vertical lines used as a        reference) to provide representational geographic information        (which may be used “as is” for an input image or as an overlay        for an acquired “real world” scene, drawing, map, etc.). An        exemplary grid 1500, overlaid on construction/engineering        drawing 1300, is shown in FIG. 15. It should be appreciated that        the grid 1500 may itself serve as the input image (i.e., a        “bare” grid), or be used together with another underlying input        image;    -   “Bare” data representing geo-encoded information (geographical        data points) and not necessarily derived from an        acquired/captured real-world scene (e.g., not pixel information        from a digital camera or other digital image acquisition        device). Such “bare” data may be nonetheless used to construct a        displayed input image, and may be in any of a variety of        computer-readable formats, including XML); and    -   Photographic renderings/images, including street level (see        e.g., street level image 1600 of FIG. 16), topographical,        satellite, and aerial photographic renderings/images, any of        which may be updated periodically to capture changes in a given        geographic area over time (e.g., seasonal changes such as        foliage density, which may variably impact the ability to see        some aspects of the image).

It should also be appreciated that source data representing an inputimage may be compiled from multiple data/information sources; forexample, any two or more of the examples provided above for input imagesand source data representing input images, or any two or more other datasources, can provide information that can be combined or integrated toform source data that is electronically processed to display an image ona display device.

As noted above, in some implementations an input image may be indexed toGlobal Positioning System (GPS) coordinates or another coordinate systemthat provides geo-spatial positioning. An input image may includegeo-coding or other geographical identification metadata and may beprovided in any computer-readable format. An input image may alsoinclude images of map symbols, such as roads and street names, that maybe superimposed upon or displayed separately from an underlyinggeographic area when the input image is displayed on a display device.

With reference again to FIG. 1, “virtual white lines” 160 may be addedto the displayed input image 150 to graphically delimit the dig area100. Virtual white lines 160 may be added to the displayed input image150 through the use of a drawing application, or dig area marking toolapplication, which may superimpose over or otherwise display the virtualwhite lines 160 on the displayed input image 150. As used herein,“virtual white lines” may include lines, drawing shapes, shades,symbols, coordinates, data sets, or other indicators to provide one ormore indications of or delimit the dig area on a displayed input image.

The exemplary embodiments described herein may additionally communicateto the underground facility owner the marked-up images which indicatethe boundary of the dig area both graphically and as a series ofgeographical coordinates. These marked-up images and coordinates enablelocate technicians who are dispatched to locate the existing undergroundfacilities to know with precision the dig area in which excavatingactivities are planned to occur regardless of whether physical whitelines exist or whether a description of the area has been accuratelyprovided. Implementations described herein may give excavators theability to provide one call centers with virtual white lines as part ofa locate request. Other implementations may provide virtual white linesto facility owners subsequent to the initial locate request to the onecall center.

Use of virtual white lines, as described herein, eliminates theuncertainty associated with imprecise excavator locate requests. Thisensures that underground facility owners determine the presence of theirunderground facilities within a correctly communicated and certain digarea and mark the location of their facilities where excavators in factplan to excavate. The precision and permanency of virtual white linesmay reduce the occurrence of underground facilities not being markedwithin a dig area. Also, use of virtual white lines may result in lessfield communication between excavators and locate technicians aboutimprecise dig area descriptions and may reduce confusion about the exactlocation of a dig area. Confusion about precise dig area locations canresult in costly damages to underground facilities which may imperil thegeneral public. When excavators inadvertently excavate at locationswhere underground facility owners have not located existing undergroundfacilities, damages to underground facilities are highly likely.Additionally, in jurisdictions where excavators are required tophysically “white line” the dig area, implementations described hereinmay enable excavators (if they so choose and are permitted to do so) toidentify the dig area boundaries with precision without being requiredto physically visit the site. The digital description of the dig area,on a displayed and marked-up input image as generated by exemplaryembodiments described herein, also creates a permanent record of the digarea that is associated with each locate request by an excavator.

Exemplary Network

FIG. 2 is a diagram of an exemplary network 200 in which systems andmethods described herein may be implemented. As shown in FIG. 2, thenetwork 200 may include a user device 210 connected to a central server220 and an image server 230 via a network 240. A single user device 210,central server 220, and image server 230 have been illustrated asconnected to network 240 for simplicity. In practice, there may be moreor fewer user devices and/or servers. For example, in one alternativeimplementation, the user device 210 may operate as a comprehensivedevice and, thus, the network 200 may include no central server, withuser device 210 communicating directly through network 240 to imageserver 230. Also, in some instances, the user device 210 may perform oneor more of the functions of the central server 220 and/or central server220 may perform one or more of the functions of the user device 210. Instill another implementation, multiple user devices 210 may be connectedto the central server 220 through the network 240.

The user device 210 may encompass a computer device, such as laptopcomputer 170, a personal computer, a tablet device, a personal digitalassistant (PDA), a cellular radiotelephone, a mobile computing device, atouch-screen device, a touchpad device, or generally any deviceincluding, or connected to, a processor and a display. The user device210 may be portable so as to be separately carried by the user at aprospective dig area. Alternatively, the user device 210 may beintegrated with or affixed to another moveable object, such as avehicle. In other implementations, the user device may be a desktop orlaptop computer located at, for example, an office of an excavatingcompany. In another implementation, the user device may be a computerlocated at the one call center, to be used by, for example, a one callcenter representative or another person present at the one call center.

The central server 220 may include a computer device that may storeinformation received from or provided to the user device 210 and/or theimage server 230. The central server may be maintained by, for example,a one call center. In some implementations, central server 220 may be aweb-based server to facilitate a remote interface through, for example,an Internet browsing application on user device 210. The central server220 may include storage capacity and/or optionally include networkedaccess to one or more separate hardware components, such as image cache235, to store cached images and the like. Central server may also storeapplications, such as image drawing applications, that can be accessedby user device 210 to manipulate the cached images.

The image server 230 may include a computer device that may store andprovide input images (source data representing input images) ofgeographic locations. The image server 230 may be associated with thesame, or a different, party that maintains the central server 220. Forexample, the image server 230 may be associated with a party thatprovides input images for a fee. In some implementations, the inputimages provided by the image server may be of sufficient resolution tobe useful to effectively delimit a dig area on the image. The inputimages from the image server 230 may include geocoding or othergeographical identification metadata and may be provided in anycomputer-readable format, such as JPEG file interchange format (JPEG),tagged image file format (TIFF), portable document format (PDF),graphics interchange format (GIF), bitmap (BMP), portable networkgraphics (PNG), Windows® metafile (WMF), Extensible Markup Language(XML) and/or the like. Also, input images from the image server 230 mayinclude a combination of images or overlays, such as overlays of streetnames, regions, landmark descriptions, and/or other information aboutareas displayed in an image. The input images from the image server 230may be supplied by a third-party provider if the coverage area of thethird-party image provider overlaps with the desired area of the user.

The network 240 may include a local area network (LAN), a wide areanetwork (WAN), a telephone network, such as the Public SwitchedTelephone Network (PSTN) or a cellular network, an intranet, theInternet, one or more communications links, or a combination ofnetworks. The user device 210, central server 220, and image server 230may connect to the network 240 via wired and/or wireless connections.The user device 210, central server 220 and image server 230 maycommunicate using any communication protocol.

Exemplary User Device Architecture

FIG. 3 is a diagram of exemplary components of user device 210. Userdevice 210 may include a bus 310, a processing unit 320, a memory 330,an input device 340, an output device 350, a location identificationunit 360, and a communication interface 370. In another implementation,user device 210 may include more, fewer, or different components. Forexample, location identification unit 360 may not be included, orlocation identification unit 360 may be included as a device locatedexternal to user device 210, such as a device worn or carried by a userof user device 210.

Bus 310 may include a path that permits communication among thecomponents of user device 210. Processing unit 320 may include aprocessor, a microprocessor, or processing logic that may interpret andexecute instructions. Memory 330 may include a random access memory(RAM), a read only memory (ROM), a memory card, a magnetic and/oroptical recording medium and its corresponding drive, or another type ofmemory device. Generally, memory 330 may be sufficient to store andmanipulate input images, such as those stored in a local image cache335. In one implementation, local image cache 335 may include one ormore input images of a dig area to be marked by a user. In anotherimplementation, local image cache 335 may include a series of inputimages that correspond to the geographical region to which a particularuser is assigned. For example, local image cache 335 may include acollection of high-resolution images of a particular zip code or town.In a further implementation, local image cache 335 may include inputimages of previously-delimited dig areas, such as dig areas where a userof user device 210 has previously requested locate operations. In stillanother implementation, local image cache 335 may include an entire setof input images intended to be made available to multiple users.

Input device 340 may include one or more mechanisms that permit a userto input information to user device 210, such as a keyboard, a keypad, atouchpad, a mouse, a stylus, a touch screen, a camera, or the like.Alternatively, or additionally, input device 340 may include amicrophone that can capture a user's intent by capturing the user'saudible commands. Alternatively, or additionally, input device 340 mayinteract with a device that monitors a condition of the user, such aseye movement, brain activity, or heart rate. Output device 350 mayinclude one or more mechanisms that output information to the user, suchas a display, a speaker, or the like.

Location identification unit 360 may include a device that can determineits geographic location to a certain degree of accuracy, such as aglobal positioning system (GPS) or a global navigation satellite system(GNSS) receiver. In another implementation, location identification unit360 may include a device that determines location using anothertechnique, such as tower (e.g., cellular tower) triangularization.Location identification unit 360 may receive location tracking signals(e.g., GPS signals) and determine its location based on these signals.In one implementation, location identification unit 360 may be capableof determining its location within approximately thirty centimeters orless. In another implementation, location identification unit mayreceive and store location coordinates from an external device.

Communication interface 370 may include any transceiver-like mechanismthat enables user device 210 to communicate with other devices and/orsystems. For example, communication interface 370 may include mechanismsfor communicating with another device or system via network 240. Forexample, communication interface 370 may enable communications betweenuser device 210 and central server 220 and/or image server 230 overnetwork 240.

As will be described in detail below, user device 210 may performcertain operations relating to the documentation of locate requestsand/or the creation of virtual white lines. User device 210 may performthese operations in response to processing unit 320 executing softwareinstructions contained in a computer-readable medium, such as memory330. A computer-readable medium may be defined as a physical or logicalmemory device.

The software instructions may be read into memory 330 from anothercomputer-readable medium, or from another device via the communicationinterface 370. The software instructions contained in memory 330 maycause processing unit 320 to perform processes that will be describedlater. Alternatively, hardwired circuitry may be used in place of, or incombination with, software instructions to implement processes describedherein. Thus, implementations described herein are not limited to anyspecific combination of hardware circuitry and software.

Exemplary Central Server Architecture

FIG. 4 is a diagram of exemplary components of central server 220.Central server 220 may include a bus 410, a processing unit 420, amemory 430, an input device 440, an output device 450, and acommunication interface 460. In another implementation, central server220 may include more, fewer, or different components.

Bus 410 may include a path that permits communication among thecomponents of central server 220. Processing unit 420 may include aprocessor, a microprocessor, or processing logic that may interpret andexecute instructions.

Memory 430 may include a magnetic and/or optical recording medium andits corresponding drive, a RAM, a ROM, a memory card, or another type ofmemory device suitable for high capacity data storage. Generally, memory430 may be sufficient to store input images of particular geographiclocations, such as those stored in a central image cache 435. In oneimplementation, central image cache 435 may include a set of inputimages that correspond to the geographical regions to which a group ofusers are assigned. In still another implementation, central image cache435 may include the entire set of input images intended to be madeavailable to any of a group of users. For example, central image cache435 may include a collection of high-resolution input images of aparticular county, state or other geographic region. In anotherimplementation, as shown in FIG. 2, central image cache 435 may bereplaced or supplemented with one or more networked storage components,such as image cache 235.

Input device 440, similar to input device 340 of user device 210, mayinclude one or more mechanisms that permit an operator to inputinformation to central server 220. Output device 450 may include one ormore mechanisms that output information to an operator of the centralserver, such as a display, a speaker, or the like.

Communication interface 460 may include any transceiver-like mechanismthat enables central server 220 to communicate with other devices and/orsystems. For example, communication interface 460 may include mechanismsfor communicating with another device or system via network 240. Forexample, communication interface 460 may enable communications betweencentral server 220 and user device 210 and/or image server 230 overnetwork 240.

As will be described in detail below, central server 220 may performcertain operations to facilitate the documentation of locate requestsand/or virtual white lines and to disseminate locate requests (andcorresponding virtual white line information) to appropriate locatetechnicians and/or other parties. Central server 220 may perform theseoperations in response to processing unit 420 executing softwareinstructions contained in a computer-readable medium, such as memory430.

The software instructions may be read into memory 430 from anothercomputer-readable medium, or from another device via communicationinterface 440. The software instructions contained in memory 430 maycause processing unit 420 to perform processes that will be describedlater. Alternatively, hardwired circuitry may be used in place of or incombination with software instructions to implement processes describedherein. Thus, implementations described herein are not limited to anyspecific combination of hardware circuitry and software.

Exemplary Routines

FIG. 5 is a diagram of exemplary software routines for central server220 and user device 210. Central server 220 may include an imageretrieval routine 520, a central image cache routine 510, a dataextraction routine 530, and a ticket manager routine 540. User device210 may include a image request routine 550, an image display routine560, and a user input routine 570. As discussed in more detail herein,the examples of routines associated with central server 220 and userdevice 210 may be interchangeable between central server 220 and userdevice 210. Furthermore, some or all of routines 510, 520, 530, 540,550, 550, 560, and 570 need not be performed exclusively by any one ofcentral server 220 or user device 210. FIG. 5 indicates communicationbetween user device 210 and facility owner 580 and/or image server 230passes through central server 220. However, it should be noted that inother implementations facility owner 580 and/or image server 230 maycommunicate directly with user device 210.

Generally, in one implementation, user device 210 may permit a user,such as an excavator or a person at a one call center, to receive aninput image and submit virtual white line information in associationwith a locate request placed to a one call center. Central server 220may permit the one call center to associate the virtual white lineinformation with the locate request and to provide instructions to afacility owner 580 who is required to conduct a locate. Instructionsfrom the one call center (via, for example, central server 220) to thefacility owner 580 may be provided as a compilation of information,called a “locate request ticket.” The virtual white line information maybe associated with the locate request ticket in the form of, forexample, a marked-up input image and/or geographic coordinates of thevirtual white lines. Facility owner 580 may be a facility owner,facility operator, or any contracted representative acting on theirbehalf.

Central image cache routine 510, image retrieval routine 520, dataextraction routine 530, and ticket manager routine 540 of central server220 may include a variety of functionalities. In certainimplementations, central image cache routine 510 may receive informationabout specific locate requests and parse each locate request in order todiscern location information. For example, a locate request may identifythe property associated with a dig area by an address of the property, anearby street intersection, or by geographic coordinates. The locaterequest might also specify, for example, the description of the dig areato be delimited, and the day and/or time that excavations are scheduledto begin.

Central image cache routine 510 may also convert location informationfor the property associated with the dig area to latitude/longitudecoordinates or geo-positioning coordinates. When location informationfrom a locate request is sufficiently precise to allow foridentification of corresponding imagery associated with propertysurrounding a dig area, central image cache routine 510 may calculatethe image extent (which may be generally defined as the bounding regionof the property of interest), and generate a locate request ticket forthe facility owner with the calculated extent. The image extent may, forexample, include the coordinates of the corners of the bounding region(e.g., the lower left x and y coordinates and the upper right x and ycoordinates). In one implementation, central image cache routine 510 maydetermine an image date, coordinates, and resolution of each image thatmay be stored in central image cache 435 or in another location. Inanother implementation, when location information from a ticket isimprecise (or “fuzzy”), central image cache routine 510 may mark thelocate request ticket to indicate that no corresponding image was ableto be retrieved based on the locate request.

Image retrieval routine 520 may catalog and store images from imageserver 230 to central server 220. For example, images may be stored incentral image cache 435 in memory 430 of central server 220. In oneimplementation, image retrieval routine 520 may query central imagecache 435 or other cache for an image associated with a particularplanned dig area relating to a locate request, and determine, based on(for example) the age and resolution of the cached image, whether theimage in central image cache 435 needs to be updated from image server230.

In another implementation, image retrieval routine 520 may interfacewith multiple image providers and/or image servers 230. Image retrievalroutine 520 may determine which image provider is the best source forthe image corresponding to a particular dig area relating to a locaterequest based on algorithms that factor, for example, each imageprovider's geographical coverage, image resolution, cost, andavailability. Regarding geographical coverage, it will be beneficial toconfirm that the image provider's area of coverage includes the desiredextent.

Regarding image resolution, available resolution may be measured inmeters (or centimeters, feet, or inches) per pixel. For example, oneprovider may offer thirty centimeters per pixel, while another offersfifteen centimeters or less per pixel, for the same coverage area. If animage is requested at a standard altitude, then image retrieval routine520 may choose a pre-defined optimal scale (for example, thirtycentimeters per pixel for a rural area, but fifteen centimeters perpixel for an urban area) and determine which provider provides images atthe pre-defined optimal scale. Alternatively, if the image of interestis at a less granular scale (for example, a community or neighborhoodimage that allows the locator to pan around the image), then resolutionmay not be a significant factor.

Regarding cost, image retrieval routine 520 may have access to pricinginformation for a variety of image providers. Image retrieval routine520 may identify which provider has the lowest cost for the desiredimage. Cost analysis may be based on images desired for an individualticket or the algorithm may account for a group of image requests,including volume incentives and/or penalties from each image provider.

Regarding availability of image providers, image retrieval routine 520may identify what providers are available and/or operational. Also, ifan image provider has a regular latency profile (for example, if aprovider has a particular server that is busiest 3-5 PM Pacific time),then image retrieval routine 520 may manage requests to be provided toanother image provider or to a particular server of that image providerto efficiently load share the image retrieval.

When an image provider is selected, image retrieval routine 520 maydownload the image from the selected image provider's server, which maybe image server 230. The downloaded image may be stored locally, forexample, in the central image cache 435.

It should be understood that some of the routines and/or functionalitiesdescribed above with respect to central image cache routine 510 andimage retrieval routine 520 may be performed by one or both of theroutines 510 and 520 above, and the arrangement of functionalities arenot limited to the implementations disclosed herein.

In certain implementations, data extraction routine 530 may obtaingeographic coordinates (e.g., Global Positioning System (GPS)coordinates, other geo-positioning coordinates, or latitude andlongitude coordinates) based on a marked-up input image provided by, forexample, user input routine 570 in user device 210. Marked-up inputimages may also include text or other indicators including, for example,text blocks describing the dig area; offsets to environmental landmarks;a locate request ticket number; the address or lot number of the digarea; and/or the date, time, and purpose of the excavation. Thisadditional data may also be extracted from the input image and stored asa dataset associated with the marked-up input image.

In one implementation, central server 220 may interface with a ticketmanagement program for coordinating multiple locate request tickets andfor providing locate request information to a facility owner 580. Ticketmanager routine 540 may facilitate such an interface. The ticketmanagement program for coordinating multiple tickets may also reside oncentral server 220, for example, or on a separate server that isaccessible to central server 220. Generally, locate request ticketinformation may be stored on central server 220 and disseminated to afacility owner 580. When a user submits a locate request, the user mayalso subsequently submit a set of virtual white lines on an input imageto associate with the locate request. In another implementation, theuser may submit a set of virtual white lines on an input imagesimultaneously with the user's initial locate request. The ticketmanager routine 540 may allow the user to update data regarding thelocate request and to synchronize the images and user input. Ticketmanager routine 540 may send virtual white lines from central server 220to facility owner 580 for locate request tickets that need to becompleted, and will copy the input from facility owner 580 to centralserver 220 for completed tickets. Ticket manager routine 540 mayinterface with the routines described above to correlate assigned locaterequest tickets with images and virtual white lines for those ticketsand download the images to facility owner 580 from central server 220.

Referring now to routines in FIG. 5 that may be associated with userdevice 210, image request routine 550 may solicit information from auser as the basis of an image to associate with a dig area for a locaterequest. For example, the user input may include a postal address, lotnumber, plat number, street intersection, a set of GPS coordinatesrelating to the planned dig area, or the like. The user device may sendthe location information to central server 220 to allow the centralserver (via, for example, image retrieval routine 520) to identify acorresponding image.

In one implementation, image request routine 550 may identify an imageto retrieve based on GPS coordinates of a GPS-enabled device associatedwith a user. For example, a user may arrive at an excavation site in aGPS-enabled vehicle and the GPS information from the vehicle may be usedto identify coordinates corresponding to an image to be retrieved. GPScoordinates may also be obtained from other GPS-enabled devices beingused by or in the vicinity of the user. As used herein a GPS-enableddevice may include any device or combination of devices capable ofinterfacing with a global navigation satellite system, geo-spatialpositioning system, or other location-identification system to determinea location. Examples of GPS-enabled devices may include a marking device(e.g., a paint wand) with an integrated GPS receiver; a locating device(e.g., a locating wand) with a GPS receiver; a wearable GPS-enableddevice; a vehicle-mounted GPS system; certain PDAs, computers, andcellular telephones; and stand-alone GPS-enabled systems.

In another implementation, a user may provide a street address or otherproperty identification information. If the street address or otherproperty identification information is insufficient to identify aspecific property, image request routine may (by, for example,communicating with central server 220) suggest a list of possiblematches or suggest another form of information suitable for identifyingthe property associated with a planned dig area.

In still another implementation, image request routine 550 may identifyone or more images to request based on a designated geographical areaassigned to a user. For example, a user may be assigned to work inseveral dig areas associated with a particular section of aneighborhood. The user may input coordinates associated with the entireselected section of the neighborhood, and central image cache routine510 and/or image retrieval routine 520 may then retrieve images forthose coordinates.

Once an image is loaded from local cache 335 and/or central server 220,image display routine 560 may provide a variety of view options for theuser. For example, image display routine 560 may support zooming in andout of the image by changing the image scale. Also, image displayroutine 560 may support panning horizontally and vertically in theimage. Furthermore, image display routine 560 may support “roaming”outside the boundaries of the initial extent. Roaming generally occurswhen the user zooms or pans, such that images beyond the boundaries ofthe stored images may be required to be retrieved from either localimage cache 335 or central server 220. The additional images retrievedfrom either local image cache 335 or central server 220 may be displayedand stitched together to display a complete image.

User input routine 570 allows the user to add information to the imageto delimit a planned dig area. User input routine 570 may accept userinput from, for example, input device 340, and may support the additionof lines, freehand forms (or scribbling), shading, drawing shapes suchas circles and rectangles, or other markings which delimit theapproximate location of the dig area. As used herein, a drawing shapemay generally be any kind of drawing shape or mark. In addition to thedelimiting of the dig area on the input image, user input routine 570may also include offsets from environmental landmarks that may bedisplayed on the image in, for example, English or metric units.Environmental landmarks may also be marked and/or highlighted on theinput image. An environmental landmark may include any physical objectthat is likely to remain in a fixed location for an extended period oftime. Examples of an environmental landmark may include a tree, a curb,a driveway, a utility pole, a fire hydrant, a storm drain, a pedestal, awater meter box, a manhole lid, a building structure (e.g., aresidential or office building), or a light post. For example, an edgeof a dig area located two and a half meters behind the curb of aresidential street would be documented as being offset two and a halfmeters behind the curb.

In one implementation, there may be occasions where central server 220is unable to provide an input image representing a “real-world” scene toassociate with location information for a planned dig area. Instead,user input routine 570 may still be utilized with an input imageconstituted by a grid (e.g., a “blank” grid) that provides geographicreference points. For example, the user may use drawing tools in userinput routine 570 to sketch environmental landmarks and virtual whitelines on an input image constituted by a blank grid, and a marked-upimage thusly generated is nonetheless sufficient to delimit a dig area.

User input routine 570 may also accept positioning information fromexternal sources, such as a GPS-enabled device. In one implementation,where a blank grid is being used, the positioning information may beuploaded to the blank grid to provide, for example, points for relativespacing, proper scale, and dimensioning of a user's sketch.

In another implementation, user device 210 may also communicate withexternal components to identify geographical positioning coordinates ofvarious points related to a dig area, such as dig area boundaries,environmental landmarks, and the like. Particular coordinates may bestored in a memory of the external device, sent to user device 210, andprovided as information on the input image using, for example, userinput routine 570. The coordinates may appear, for example, as dots onthe input image that can be connected or labeled by the user using userinterface 570.

User input routine 570 may further include features to annotate theimage with text and to revise user inputs by, for example deleting,dragging or pasting drawing shapes. In one implementation, when the userzooms the image view in or out, user input (e.g., lines and/or shapes)that have been added to the original image may adhere to the changingimage scale and remain in the original user-input locations.

The virtual white lines, which may be a compilation of the input imageand user inputs, may be saved as an image file. In anotherimplementation, the user inputs may be saved in a marked-up format,including the geo-coordinates of each drawing shape added to the imageby the user.

FIG. 6 provides a flow diagram 600 of exemplary activities of centralserver 220 for managing a locate request according to an implementation.In another implementation, at least some of the blocks of flow diagram600 may be performed using user device 210. In another implementation,one or more of the blocks of FIG. 6 may be manually performed orperformed by other devices.

Flow diagram 600 may begin an excavator contacts a one call center toplace a locate request. The user (e.g., the excavator or a person at theone call center) may use a computer or other user device 210 to submitthe locate request to central server 220. Central server 220 mayinclude, generally, a virtual white line application and image storageservice to facilitate locate requests. In one implementation, the usermay be required to establish an account with central server 220, whichmay include providing a log-in identifier and password. Anotherimplementation may allow for access to central server 220 without anaccount. As part of the locate request, the user (via user device 210)may provide to central server 220 a geographic location or addressassociated with a planned dig area. The geographic location or addressmay be extracted from the locate request, so that the server may receivethe dig area location information (block 610).

In block 620, input image coordinates may be associated with thegeographic location or address information. For example, central server220 may associate coordinates of an input image with the generallocation of the planned dig area that was provided in the locaterequest. Such association may include associating the address withgeographic location information that has a defined image extent, such asglobal positioning coordinates for the image extent corresponding to theproperty address.

In block 630, a stored input image associated with the address may beretrieved from a cache of images and provided to the user device 210. Aspreviously described discussed herein with respect to FIG. 5, the cacheof images may reside within central server 220, a separate image server,or another storage device. Central server 220 may determine if thecentral image cache 435 (or other image cache) already has an inputimage stored for the dig area that corresponds to the calculated imageextent. If so, central image cache 435 may return the stored input imageto central server 220. If central image cache 435 does not have acorresponding input image, then a determination may be made whether toobtain an updated image from image server(s) 230.

Central server 200 may send the particular image associated with theaddress to the user device (block 640). Along with the image, thecentral server 220 may provide a dig area marking tool application to abrowser at user device 210. Aspects of drawing virtual white lines withthe dig area marking tool application are described further with respectto FIG. 7 below. It should be noted that blocks 610 through 640 may bean iterative process. Also, if a user does not have a particularaddress, it may be possible to pan around a high-level (e.g., lowerresolution) input image to eventually identify a more specific locationassociated with a planned dig area.

After a user had added virtual white lines and any additionalinformation to the image, the edited image and other information tocomplete the locate request may be sent from the user device 210 andreceived by central server 220 (block 650). If not previouslyaccomplished by the user device, central server 220 may convert thevirtual white lines to geographic coordinates (block 660). Morespecifically, the central server 220 may determine geographiccoordinates (e.g., Global Positioning System (GPS) coordinates orlatitude and longitude coordinates) of the dig area based on virtualwhite lines on the marked-up digital map.

In block 670, the central server 220 may associate the locate requestwith the mark-up image and coordinates of the virtual white lines. Uponreceipt of the marked-up input image from user device 210, centralserver 220 may forward the marked-up version of the input image tomemory 430 (or another memory location) for storing in association withthe locate request ticket information. The marked-up input image maysubsequently be provided to an underground facility owner that willascertain the location of any underground facilities within or near thedig area. Central server 210 may provide the marked-up input image(including geographic coordinates and other locate request information)to the underground facility owner(s) that will perform the undergroundfacility locate operation. The locate request and virtual white linesmay be sent to the facility owner 580 (block 680). The information maybe provided via an electronic or tangible delivery system, which mayinclude, for example, email, a webpage, facsimile, automated telephoneservice, printer, automated mailing, or other form of communication.

While the flow diagram of FIG. 6 is described in the context of anexcavator contacting a one call center, other implementations may occurin the context of an excavator contacting a facility owner directly toplace a locate request. In another implementation, a one call center maycontact a facility owner to transmit a locate request. In still anotherimplementation, the one call center representative may draft virtualwhite lines based on input from an excavator.

FIG. 7 is a flow diagram 700 of exemplary activities of user device 210for submitting a locate request. User device 210 may first request fromcentral server 220 an input image that corresponds to an address orother location information for a planned dig area (block 710). In block720, user device 210 may receive the input image and allow a user toconfirm that the input image properly corresponds to the actual locationof the dig area. Along with the image, the user device 210 may receive adig area marking tool application to allow a user to add data to theimage. As noted above with respect to FIG. 6, the requesting (block 710)and receiving (block 720) of the input image may be an iterative processand may allow for panning a high level-input image to identify aparticular dig area location.

Once an acceptable image is received at user device 210, user device 210may associate the locate request data with the input image (block 730).The locate request data may include, for example, a locate requestticket number, an address of the dig area, and/or the date, time, andpurpose of the excavation. Some or all of the locate request data may beincluded as metadata with the input image or otherwise associated withthe image.

In block 740, virtual white lines may be added to the input image thatwas received previously in block 720. The information about theapproximate geographic location of the dig area may be input by the userusing the dig area marking tool application and an input device, such asinput device 340 (FIG. 3) of user device 210. Additional aspectsregarding use of the dig area marking tool are discussed in more detailbelow with respect to FIG. 9.

Still referring to block 740, information about the approximategeographic location of the dig area may also be received directly from aGPS-enabled device, such as the GPS-enabled locating device or markingdevice used in block 630, and added to the retrieved image. For example,the approximate geographic location of the physical dig area white linesmay be determined by identifying the current geographic location of aGPS-enabled device as it is located at points on the physical whitelines of the dig area. In one implementation, the GPS-enable device maybe a marking tool that stores the GPS coordinates of the marking tool asa user applies the physical white lines. The information from theGPS-enabled device may be communicated to user device 210 or centralserver 220 to be associated with the input image. The user may use acombination of received GPS information and manual entries to createvirtual white lines for the dig area.

In block 750, information about offsets of the dig area fromenvironmental landmarks may, if necessary, be added to the stored inputimage that was retrieved previously in block 630. As with the input ofthe virtual white lines in block 640, the location of the environmentallandmarks may be input by the user using an input device, such as inputdevice 340 (FIG. 3) of user device 210, or automatically input from aGPS-enabled device. The environmental landmark may be marked and/orlabeled as an existing object shown on the input image, or theenvironmental landmark may be a separate item (e.g., not shown on theinput image) that is added by the user. The offset information may beautomatically calculated or input by the user. Offset information mayalso be obtained by identifying selected environmental landmarks on theretrieved image and automatically calculating the distance from theselected environmental landmarks to the virtual white lines added to theimage.

In block 760, information about the location of the virtual white linesmay, if necessary, be converted to GPS coordinates. The location of thevirtual white lines and/or landmarks shown on the input image may beassociated with approximate GPS (or other geographic) coordinates basedon the geo-coding of the input image. Thus, in some implementations theGPS coordinates of the virtual white lines may be available toapproximately delimit the dig area independent of the stored inputimage. In block 770, the retrieved input image and information about thelocation of the virtual white lines may be stored in memory as a singleimage. The single image may be stored as, for example, a digital imageor an interactive electronic map. Additionally or alternatively, inblock 780, the geographic coordinates of the virtual white lines may bestored in memory, such as memory 330 (FIG. 3), as a separate data set.The data set may be compiled as, for example, a database of GPScoordinates and other information relevant to the locate request. Anexemplary data set of the information that may be provided is describedin more detail with respect to FIG. 8. In block 790, the single imageand/or separate data set may be transmitted to a central location, suchas central server 220 (FIG. 2).

FIG. 8 is a diagram of an exemplary data set 800 that may be stored inmemory 330 and/or transmitted to central server 220. Some of theinformation in data set 800 may be automatically populated by a softwareprogram on user device 210 or central server 220, such as the dig areamarking tool application or a related application. As shown in FIG. 8, adata set 800 may include a timestamp field 810, an excavator identifierfield 720, a dig area coordinates field 830, an environmental landmarkidentifier field 840, an environmental landmark location field 850, another information field 860, a property address field 870, and a ticketnumber field 880. In another implementation, the data set 800 mayinclude additional, fewer, or different fields.

Timestamp field 810 may include time data that identifies the day and/ortime that the completed locate request was submitted. The time data intimestamp field 810 is shown in FIG. 8 as 9:43 a.m. Eastern StandardTime on Nov. 20, 2007—although any type of date and/or time code may beused. The information in timestamp field 810 may be useful inestablishing when a locate request was initiated.

The excavator identifier field 820 may include an identifier thatuniquely identifies the entity submitting the locate request. Theidentifier in excavator field 820 is shown in FIG. 8 as “Joe's PoolCenter”—although any type of identifier may be used. Virtual white linecoordinates field 830 may include geographic location informationcorresponding to the delimited dig area. In one implementation, thegeographic location information may include a set of geographic pointsalong the delimited dig area. The geographic location information invirtual white line coordinates field 830 is shown in FIG. 8 asN38°51.40748, WO77°20.27798; . . . ; N38°51.40784,WO77°20.27865—although any type of geographic location information maybe used. The information in virtual white line coordinates field 830 maybe useful in graphically presenting the dig area on a map, and/or toverify that the dig area was accurately delimited with physical whitelines.

Environmental landmark identifier field 840 may include an identifierthat uniquely identifies the type of environmental landmark beingmarked. The identifier in environmental landmark identifier field 840 isshown in FIG. 8 as “curb”—although any type of identifier may be used.Environmental landmark location field 850 may include geographiclocation information corresponding to the environmental landmarkidentified in environmental landmark identifier field 840. Thegeographic location information in environmental landmark location field850 is shown in FIG. 8 as N38°51.40756, WO77°20.27805; . . . ;N38°51.40773, WO77°20.27858—although any type of geographic locationinformation may be used.

Other information field 860 may store other data that may be useful,including user notes, such as distance information that identifies adistance between one or more environmental landmarks and one or moreboundaries of the dig area. Other information field 860 is shown in FIG.8 as including “1.2 meters between curb and edge of dig area”—althoughany other data may be used. Additionally and/or alternatively, otherinformation field 860 may include audio/voice data, transcribedvoice-recognition data, or the like to incorporate user notes.

Property address field 870 may be the property address associated withthe dig area in the data set 800. The property address field 870 mayinclude, for example, the street address and zip code of the property.Other information in field 870 may include city, state, and/or countyidentifiers. The ticket number field 880 may include the ticket numberassociated with the locate request, such as ticket number “1234567”shown in FIG. 8. In some implementations, the ticket number may not beknown at the time the data set 800 is provided from user device 210 tocentral server 220; and, thus, the ticket number 880 may be added to thedata set 800 at a later time by the central server 220.

In one implementation, central server 220 may store multiple data setscorresponding to a single dig area. User device 210 may provide the datasets to server 220 in a batch—such as a batch corresponding to a groupof marks delimiting a single dig area—or individually. The batch may begrouped together with other information generally relating to the locaterequest, such as the name of the company responsible for performing thelocate operation, the name or other identification information of thelocate technician, and the like. Additionally, or alternatively, theother information generally relating to the locate operation may beincluded in each data set.

FIG. 9 is an exemplary diagram of a user interface 900 that may bepresented via the user device 210. The user interface 900 that may beimplemented, for example, by a browser at user device 210. Userinterface 900 may present an input image 905, along with a image scale910 overlaying input image 905, and may also include various palettes,toolbars, or other interfaces that enable the user to manipulate (e.g.,zoom in, zoom out) and/or mark up the input image. For example, userinterface 900 may include a marking palette 915, a sketching palette 920and a navigation palette 925. Marking palette 915 may group userinterface buttons that the user can select (using, for example, theinput device 340) in order to draw certain shapes (e.g., a polygon, arectangle or a circle) or to orient or annotate the input image. Markingpalette 915 may include a button (e.g., text button) that permits theuser to add text boxes that can be used to add textual content forannotating the input image. Sketching palette 920 may group userinterface buttons that the user can select in order to draw virtualwhite line shapes on input image 905. Sketching palette 920 may include,for example, a freehand button that permits the user to draw virtualwhite lines freehand, or a line button that permits the user to drawstraight lines on input image 905. Navigation palette 925 may group userinterface buttons that the user can select in order to zoom or pan theinput image (e.g., zoom in, zoom out, zoom to, pan, pan left, pan right,pan up, pan down, etc.). Navigation palette 925 may additionally includeone or more buttons that enable user drawn shapes to be accentuated(e.g., grayscale, transparency, etc.). The exemplary user interface 900of FIG. 9 additionally depicts an example circular virtual white line930 that has been drawn on input image 905. FIG. 9 also depicts anexample rectangular virtual white line 935 being drawn on map 905 usinga line cursor 940.

CONCLUSION

Aspects of the invention as described herein enable a user (e.g., anexcavator) to delimit a dig area when placing a locate request with, forexample, a one call center. A server at the one call center may retrievefrom a database the appropriate input image of a specific geographiclocation corresponding to a planned dig area where locate operations areto be conducted for underground facilities. The retrieved input image isprovided to the user so that the user may draft, on the retrieved image,the approximate geographic boundaries of the planned dig area. Thecombination of the retrieved image and additional information drafted bythe user may be saved in a variety of formats as virtual white lines.Other information regarding the specific geographic location of the digarea boundaries and environmental landmarks may be incorporated into thevirtual white lines using direct input from GPS-enabled positioningtools and the like.

In other implementations, a user may interface directly with a facilityowner to provide a virtual white line image—eliminating the involvementof the one-call center. In such an implementation, functionalities ofthe one call center for enabling the user of virtual white lines may beassumed by the facility owner and or the user.

Virtual white lines delimiting a dig area may serve several purposes.For example, virtual white lines as described herein may enhanceexcavators' safety and protect the general public from risks associatedwith damage to underground facilities by ensuring locate techniciansreceive clearly-communicated boundaries for their locate operations.Furthermore, virtual white lines may enhance the completeness of locateoperations ensuring that excavators do not excavate where locates havenot been performed. Also, the virtual white lines may providesignificant improvements in accuracy. In contrast, translation oftextual descriptions of a dig area may be time consuming and imprecise.For example, a telephone call to a one call center may require anoperator to transcribe an audible description of a planned dig area. Thetranscription may be eventually provided to a locate technicianperforming a locate operation of underground facilities. However,transcribed verbal descriptions of a location may lack precision,possibly communicating to a locate technician incorrect bounds of thedig area intended by the excavator, creating a significant risk ofdamage to underground facilities. As another benefit, virtual whitelines as described herein may enable excavators to identify dig areaboundaries with precision without being required to physically visit adig area. Thus, an excavator may be able to save time and resources byeliminating certain trips to a dig area. Additionally, or alternatively,use of virtual white lines may provide for easier dissemination. Inputimages with virtual white lines can be associated with individualtickets and recalled electronically, avoiding the uncertainties anderrors associated with manual filing systems.

The foregoing description is not intended to be exhaustive or to limitthe description to the precise form disclosed. Modifications andvariations are possible in light of the above disclosure or may beacquired from practice of the invention.

For example, certain information has been described as being presentedvisually on a screen of user device 210. In other implementations, thisinformation may be audibly provided to the user. Also, particularinformation has been described as being input via an input device 340,such as a screen of user device 210. In other implementations, thisinformation may be provided in other ways, such as by receiving inputsvia input keys and/or buttons, by recognizing speech of the user, or bymonitoring a condition of the user. More particularly, input device 340may be capable of capturing signals that reflect a user's intent. Forexample, input device 340 may include a microphone that can capture auser's intent by capturing the user's audible commands. Alternatively,input device 340 may interact with a device that monitors a condition ofthe user, such as eye movement, brain activity, or heart rate.

As another example, certain components, such as user device 210 andcentral server 220 have been described as using an image cache. In otherimplementations, user device 210 and/or central server 220 maycommunicate with an image server (such as imager server 230) inreal-time, so that no image cache may be required. In still otherimplementations, user device 210 may, for example, communicate in realtime with central server 220.

Also, implementations in FIG. 5 herein generally described processesassociating a one call center with central server 220. In anotherimplementation, facility owner 580 may provide a separate server toaccomplish some of the routines of FIG. 5. For example, a facility ownermay be informed by a one call center of a locate request that includesonly a textual description of a planned dig area. Facility owner 580 mayseparately contact the excavator (e.g., user) who placed the locaterequest and provide and conduct virtual white line procedures with theuse from a separate server, later associating the virtual white lineswith the other ticket information. In still other implementations, theuser may conduct an initial locate request in two parts by providing aconventional locate request to a one call center and then conducting avirtual white line process with a separate server operated by a facilityowner 580.

As another example, it should be noted that reference to a GPS-enableddevice is not limited to GPS systems only, and that any globalnavigation satellite system or other system that provides geo-spatialpositioning may be used in implementations of the invention.

Also, while a series of blocks has been described with regard to FIGS. 6and 7, the order of the blocks may be modified in other implementations.Further, non-dependent blocks may be performed in parallel.

Aspects, as described above, may be implemented in many different formsof software, firmware, and hardware in the implementations illustratedin the figures. The actual software code or specialized control hardwareused to implement these aspects is not limiting of the descriptionprovided herein. Thus, the operation and behavior of the aspects weredescribed without reference to the specific software code—it beingunderstood that software and control hardware can be designed toimplement the aspects based on the description herein.

Even though particular combinations of features are recited in theclaims and/or disclosed in the specification, these combinations are notintended to limit the invention. In fact, many of these features may becombined in ways not specifically recited in the claims and/or disclosedin the specification.

No element, act, or instruction used in the present application shouldbe construed as critical or essential to the invention unless explicitlydescribed as such. Also, as used herein, the article “a” is intended toinclude one or more items. Where only one item is intended, the term“one” or similar language is used. Further, the phrase “based on” isintended to mean “based, at least in part, on” unless explicitly statedotherwise.

The invention claimed is:
 1. A method for electronically delimiting adig area that is planned to be excavated or disturbed during excavationactivities, so as to facilitate detection of a presence or an absence ofat least one underground facility within the dig area, the methodcomprising: A) electronically sending from at least one communicationinterface via a network, to an excavator at a first location remote fromthe dig area, first source data representing at least one digital imageof a geographic area including the dig area; B) electronically receivingfrom the excavator, at the at least one communication interface via thenetwork, second source data representing a marked-up version of the atleast one digital image that includes at least one dig area indicatorsketched on the digital image by the excavator via a user input deviceassociated with a display device that processes the first source data todisplay the at least one digital image to the excavator at the firstlocation remote from the dig area, the at least one dig area indicatorproviding at least one unbuffered indication of a boundary of the digarea on the marked-up version of the at least one digital image, themarked-up version of the at least one digital image further including atleast one offset indicator to indicate, in the at least one digitalimage, at least one offset distance between at least one environmentallandmark in the geographic area and the boundary of the dig areaindicated by the at least one dig area indicator; C) converting, via atleast one processor, the at least one dig area indicator to a pluralityof geographic coordinates representing the boundary of the dig area; andD) providing, via an electronic delivery system, the plurality ofgeographic coordinates representing the boundary of the dig area to anentity associated with performing a locate and marking operation in thedig area to detect and mark the presence or the absence of the at leastone underground facility within the dig area, so as to reduceuncertainty or confusion about an exact location and the boundary of thedig area based at least in part on the at least one dig area indicator,and thereby facilitate the performance of the locate operation to detectthe presence or the absence of the at least one underground facilitywithin the dig area.
 2. The method of claim 1, wherein the at least onedigital image comprises a scanned or converted manual free-hand sketchof the geographic area.
 3. The method of claim 1, wherein the at leastone digital image comprises at least one map of the geographic area. 4.The method of claim 3, wherein the at least one map of the geographicarea includes one or more of: a street/road map, a topographical map, amilitary map, a parcel map, a tax map, a town or county planning map, apolygon map, and a virtual map.
 5. The method of claim 4, wherein thefirst source data representing the at least one digital image comprisingthe at least one map includes geo-encoded information.
 6. The method ofclaim 3, wherein the at least one map includes at least one facility mapillustrating at least one installed underground facility in thegeographic area.
 7. The method of claim 6, wherein the first source datarepresenting the at least one digital image comprising the at least onefacility map includes geo-encoded information.
 8. The method of claim 1,wherein the at least one digital image comprises at least onearchitectural, construction and/or engineering drawing or virtualrendition of the geographic area.
 9. The method of claim 1, wherein theat least one digital image comprises at least one land survey relatingto the geographic area.
 10. The method of claim 1, wherein the at leastone digital image comprises at least one grid to providerepresentational geographic information and a reference relating to thegeographic area.
 11. The method of claim 1, wherein the first sourcedata comprises geo-encoded information relating to the geographicalarea.
 12. The method of claim 1, wherein the first source data does notinclude pixel information from a digital image acquisition device. 13.The method of claim 1, wherein the at least one digital image comprisesat least one photographic image.
 14. The method of claim 13, wherein theat least one photographic image comprises at least one street levelphotographic image.
 15. The method of claim 13, wherein the at least onephotographic image comprises one or more of a topographical image, asatellite image, and an aerial image.
 16. The method of claim 1, whereinD) includes providing, to the entity associated with performing thelocate and marking operation, a link to a webpage at which at least oneof the second source data and the plurality of geographic coordinatesrepresenting the boundary of the dig area may be accessed.
 17. Themethod of claim 1, wherein D) includes providing, to the entityassociated with performing the locate and marking operation, a locaterequest ticket.
 18. At least one non-transitory computer-readablestorage medium encoded with instructions that, when executed on at leastone processing unit, perform a method for electronically delimiting adig area that is planned to be excavated or disturbed during excavationactivities, so as to facilitate detection of a presence or an absence ofat least one underground facility within the dig area, the methodcomprising: A) electronically sending via a network, to an excavator ata first location remote from the dig area, first source datarepresenting at least one digital image of a geographic area includingthe dig area; B) electronically receiving from the excavator, via thenetwork, second source data representing a marked-up version of the atleast one digital image that includes at least one dig area indicatorsketched on the digital image by the excavator via a user input deviceassociated with a display device that processes the first source data todisplay the at least one digital image to the excavator at the firstlocation remote from the dig area, the at least one dig area indicatorproviding at least one unbuffered indication of a boundary of the digarea on the marked-up version of the at least one digital image, themarked-up version of the at least one digital image further including atleast one offset indicator to indicate, in the at least one digitalimage, at least one offset distance between at least one environmentallandmark in the geographic area and the boundary of the dig areaindicated by the at least one dig area indicator; C) converting, via atleast one processor, the at least one dig area indicator to a pluralityof geographic coordinates representing the boundary of the dig area; andD) providing, via an electronic delivery system, the plurality ofgeographic coordinates representing the boundary of the dig area to anentity associated with performing a locate and marking operation in thedig area to detect and mark the presence or the absence of the at leastone underground facility within the dig area so as to reduce uncertaintyor confusion about an exact location and the boundary of the dig areabased at least in part on the at least one dig area indicator, andthereby facilitate the performance of the locate operation to detect thepresence or the absence of the at least one underground facility withinthe dig area.
 19. A method for electronically delimiting a dig area thatis planned to be excavated or disturbed during excavation activities, soas to facilitate detection of a presence or an absence of at least oneunderground facility within the dig area, the method comprising: A)electronically sending, from at least one communication interface via anetwork, first source data representing at least one digital image of ageographic area including the dig area; B) electronically receiving froman excavator, at the at least one communication interface via thenetwork, second source data representing a marked-up version of the atleast one digital image that includes at least one dig area indicatorsketched on the digital image by the excavator via a user input deviceassociated with a display device that processes the first source data todisplay the at least one digital image to the excavator, the at leastone dig area indicator providing at least one unbuffered indication of aboundary of the dig area on the marked-up version of the at least onedigital image, the marked-up version of the at least one digital imagefurther including at least one offset indicator to indicate, in the atleast one digital image, at least one offset distance between at leastone environmental landmark in the geographic area and the boundary ofthe dig area indicated by the at least one dig area indicator, whereinthe at least one dig area indicator is added without acquiringgeographic coordinates corresponding to the at least one dig areaindicator; C) converting, via at least one processor, the at least onedig area indicator to a plurality of geographic coordinates representingthe boundary of the dig area; and D) providing, via an electronicdelivery system, the plurality of geographic coordinates representingthe boundary of the dig area to an entity associated with performing alocate and marking operation in the dig area to detect and mark thepresence or the absence of the at least one underground facility withinthe dig area so as to reduce uncertainty or confusion about an exactlocation and the boundary of the dig area based at least in part on theat least one dig area indicator, and thereby facilitate the performanceof the locate operation to detect the presence or the absence of the atleast one underground facility within the dig area.
 20. The method ofclaim 19, wherein the at least one digital image comprises a scanned orconverted manual free-hand sketch of the geographic area.
 21. The methodof claim 19, wherein the at least one digital image comprises at leastone map of the geographic area.
 22. The method of claim 21, wherein theat least one map of the geographic area includes one or more of: astreet/road map, a topographical map, a military map, a parcel map, atax map, a town or county planning map, a polygon map, and a virtualmap.
 23. The method of claim 22, wherein the first source datarepresenting the at least one digital image comprising the at least onemap includes geo-encoded information.
 24. The method of claim 21,wherein the at least one map includes at least one facility mapillustrating at least one installed underground facility in thegeographic area.
 25. The method of claim 24, wherein the first sourcedata representing the at least one digital image comprising the at leastone facility map includes geo-encoded information.
 26. The method ofclaim 19, wherein the at least one digital image comprises at least onearchitectural, construction and/or engineering drawing or virtualrendition of the geographic area.
 27. The method of claim 19, whereinthe at least one digital image comprises at least one land surveyrelating to the geographic area.
 28. The method of claim 19, wherein theat least one digital image comprises at least one grid to providerepresentational geographic information and a reference relating to thegeographic area.
 29. The method of claim 19, wherein the first sourcedata comprises geo-encoded information relating to the geographicalarea.
 30. The method of claim 19, wherein the first source data does notinclude pixel information from a digital image acquisition device. 31.The method of claim 19, wherein the at least one input image comprisesat least one photographic image.
 32. The method of claim 31, wherein theat least one photographic image comprises at least one street levelphotographic image.
 33. The method of claim 31, wherein the at least onephotographic image comprises one or more of a topographical image, asatellite image, and an aerial image.
 34. The method of claim 19,wherein D) includes providing, to the entity associated with performingthe locate and marking operation, a link to a webpage at which at leastone of the second source data and the plurality of geographiccoordinates representing the boundary of the dig area may be accessed.35. The method of claim 19, wherein D) includes providing, to the entityassociated with performing the locate and marking operation, a locaterequest ticket.
 36. At least one non-transitory computer readablestorage medium encoded with instructions that, when executed by at leastone processing unit, perform a method for electronically delimiting adig area that is planned to be excavated or disturbed during excavationactivities, so as to facilitate detection of a presence or an absence ofat least one underground facility within the dig area, the methodcomprising: A) electronically sending via a network first source datarepresenting at least one digital image of a geographic area includingthe dig area; B) electronically receiving from an excavator, via thenetwork, second source data representing a marked-up version of the atleast one digital image that includes at least one dig area indicatorsketched on the digital image by the excavator via a user input deviceassociated with a display device that processes the first source data todisplay the at least one digital image to the excavator, the at leastone dig area indicator providing at least one unbuffered indication of aboundary of the dig area on the marked-up version of the at least onedigital image, the marked-up version of the at least one digital imagefurther including at least one offset indicator to indicate, in the atleast one digital image, at least one offset distance between at leastone environmental landmark in the geographic area and the boundary ofthe dig area indicated by the at least one dig area indicator, whereinthe at least one dig area indicator is added without acquiringgeographic coordinates corresponding to the at least one dig areaindicator; C) converting, via at least one processor, the at least onedig area indicator to a plurality of geographic coordinates representingthe boundary of the dig area; and D) providing, via an electronicdelivery system, the plurality of geographic coordinates representingthe boundary of the dig area to an entity associated with performing alocate and marking operation in the dig area to detect and mark thepresence or the absence of the at least one underground facility withinthe dig area so as to reduce uncertainty or confusion about an exactlocation and the boundary of the dig area based at least in part on theat least one dig area indicator, and thereby facilitate the performanceof the locate operation to detect the presence or the absence of the atleast one underground facility within the dig area.